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(11) | EP 0 471 429 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Drainage catheter |
| (57) A lockable sleeve drainage catheter is disclosed for percutaneous insertion into
a patient and drainage of fluid therefrom. The drainage catheter includes a flexible
distal end that is preformed for retaining the distal end of the catheter that is
inserted in the patient. For insertion, the distal end is straightened with the use
of a stiffening cannula that is inserted through the hollow passageway of the catheter.
When the catheter is inserted in the patient, the stiffening cannula is removed, and
a flexible tension member positioned within the passageway of the catheter is drawn
to position the distal end in the desired retention configuration. A lockable sleeve
positioned at the proximal end of the catheter draws the flexible tension member through
the passageway of the elongated member tube to position the distal end in the retention
configuration. The catheter also includes a locking collar at the proximal end of
the elongated member tube having an annular recess formed therein. The distal end
of the lockable sleeve includes an annular step for engaging the recess of the collar
and locking the sleeve in a fixed position relative to the elongated member tube of
the catheter. When fully extended and locked, the sleeve and elongated member form
a fluid tight interconnection. A Luer lock connector is affixed to the proximal end
of the sleeve for connection to a drainage collection system. |
[0001] This invention relates to medical devices such as catheters. Catheters can be used for draining fluids from or for applying fluid(s) to a patient.
[0002] One problem with catheters is that they can be easily dislodged and inadvertently draw side ports thereof into abdominal cavities, thereby creating severe infections.
[0003] Various catheters have been developed with so-called pigtail loops at their distal ends which both ensures drainage of the cavity and prevents accidental removal therefrom. These loops are controlled by flexible tension members held in place by retention arrangements. U.S. Patent Nos. 1,207,479 and 3,924,677 describe two forms of such retention arrangements.
[0004] Such prior art arrangements are awkward to use and could be inadvertently untied by a patient, with the possibility of the catheter being withdrawn, or partially withdrawn, from the patient.
[0006] The lockable sleeve fits over the elongated member, preferably in the region of the proximal end of the elongated member. The proximal end of the elongated member can extend through the sleeve or can be located within the sleeve.
[0007] In one embodiment, the drawable means extends through the sleeve and is attached to the proximal end of the sleeve, so that movement of the distal end of the sleeve towards the proximal end of the elongated member applies tension and activates the drawable means. In another embodiment, the drawable means can be attached to the distal end of the sleeve, in which instance the drawable means is activated by movement of the distal end of the sleeve towards the distal end of the elongated means. Clearly the drawable means can be connected to the sleeve at any convenient location.
[0008] The sleeve and elongated member can be engaged by a projection on the sleeve engaging a recess in the elongated member, or a recess in a collar about that member. The projection and recess can be interchanged, or each can have a recess with a co-operating ring which can lock into both recesses upon engagement. Clearly, other alternative locking mechanisms could be employed.
[0009] The advantages of the embodiments is that by simply moving the sleeve, the distal end of the elongated member is drawn into the pigtail configuration without the physician having to individually pull, cut or tie the free end of the flexible tension member.
Brief description of the drawings
[0011]
FIG.1 is a partially-sectioned view of a lockable sleeve drainage catheter of the present invention;
FIG.2 depicts a partially-sectioned view of the catheter of FIG.1 inserted in the bladder of a patient;
FIG.3 depicts a partially-sectioned view of the catheter of Fig.2 in a locked position;
FIG.4 depicts an alternative embodiment of the distal end of the catheter for use in the biliary system of a patient: and
FIG.5 depicts a second alternative embodiment of the distal end of the catheter for use as a gastrostomy feeding tube.
FIG.1 shows catheter 101 in an unlocked position prior to percutaneous insertion into a patient.
[0012] Depicted in FIG.2 is catheter 101 with stiffening cannula 126 inserted into bladder 102 over wire guide 103. Before insertion of catheter 101, a thin- wall needle with a stylet inserted therein (not shown) is percutaneously inserted through abdominal wall 130 into the bladder using a well-known technique. The stylet is removed, and the wire guide is inserted through the needle into the bladder. The needle is then removed with the wire guide left in place. A dilator is commonly used over the wire guide to increase the size of the puncture site. Drainage catheter 101 with a stiffening cannula inserted therein is then inserted over the wire guide into bladder 102 as shown.
[0013] As shown in FIGS.1 and 2, catheter 101 includes an elongated member 104 and a lockable sleeve 110, both formed from flexible plastic material tubes having different diameters . Flexible member 104 has a tapered distal end 105, a flared proximal end 106, and a hollow longitudinal passageway 107 therebetween. Distal end 105 is preformed into a predetermined configuration such as a well-known pigtail. A plurality of side ports 108 are formed through the wall of the elongated member about the distal end thereof for fluid such as urine to enter and drain through passageway 107. Passageway 107 also forms an opening 109 at the very distal end of the elongated member. Opening 109 permits the insertion of the catheter into a patient over the wire guide and also allows further drainage of fluid into passageway 107. However, a stiffening cannula is normally inserted through passageway 107 of the catheter to straighten the preformed distal end for percutaneous insertion over the wire guide into the bladder. When the catheter has been inserted in the bladder, the stiffening cannula and wire guide are then removed from passageway 107.
[0014] Similarly, lockable sleeve 110 has a tapered distal end 111, a proximal end 112, and a hollow longitudinal passageway 113 therebetween. By way of example, elongated member 104 is a 10.2 French polyurethane material tube approximately 32cm. in length, whereas lockable sleeve 110 is a 20 French polyurethane material tube approximately 6.5cm. in length. As shown, flared proximal end 106 of the elongated member tube and locking collar 114 affixed thereabout are positioned within sleeve passageway 113 and are longitudinally moveable therein.
[0015] The generally cylindrically-shaped locking collar includes two truncated cones 127 and 128 with beveled surfaces 115 and 116 facing the oppposite ends of the collar. Base surfaces 117 and 118 of respective cones 127 and 128 and the outside surface 119 of the collar therebetween form an annular recess, such as a groove or channel, in the collar. Lockable sleeve 110 is longitudinally moveable over locking collar 114.
[0016] Distal end 111 of the lockable sleeve includes a projection 120, such as an annular ridge or step, which extends into passageway 113 to engage the annular recess of locking collar 114. As shown, annular step 120 at the tapered distal end 111 of the sleeve is sized to snap fit into the annular recess of collar 114 when the distal end of the sleeve is longitudinally moved over beveled surface 115. As a result, annular step 120 snaps into the annular recess of the collar. The minimum dimension or diameter of passageway 113 through annular step 120 is less than the maximum dimension or diameter of outside surface 119 of the collar in the annular recess. The two dimensions are sized to form a tight fit between the annular step and recess when interconnected, which prevents the passage of fluid through the interconnection. Beveled surface 116 of the collar and flared distal end 106 of the tube further prevent the passage of fluid through the interconnection.
[0017] The drainage catheter further includes flexible tension member 121 that passes through passageways 107 and 113. Draw ports 122 and 123 are formed through the wall of the elongated member tube near drain ports 108. The flexible tension member passes from within passageway 107 through draw port 122 to the exterior of the elongated member and back into interior passageway 107 through draw port 123. The flexible tension member forms a loop through the draw ports, which is drawable to position the distal end of the elongated member tube into the desired pigtail configuration. The ends of the flexible tension member are secured to the sleeve and preferably to proximal end 112 of the lockable sleeve between the wall of the sleeve and the outside barbed surface of a well-known Luer lock connector 124. The flexible tension member, such as commercially available 4-0 Tevdek suture, is further secured between the two surfaces using, for example, Locktite 401 sealing compound.
[0018] When distal end 105 of elongated member tube 104 is fully extended for insertion into the bladder, lockable sleeve 110 is in a fully forward and unlocked position with the flared proximal end 106 of the tube positioned next to connector 124. Commonly, the Luer lock connector is formed with a taper at the distal end thereof. As a result, the flared proximal end 106 receives the tapered end of the Luer lock connector. The flared end fits against the wall of the sleeve to prevent the passage of fluid and flexible tension member therebetween.
[0019] Depicted in FIG.3 is a partially-sectioned view of drainage catheter 101 with sleeve 110 in a fully drawn and locked position and distal end 105 positioned in the pigtail configuration. The pigtail configuration at the distal end of elongated member tube 104 acts as a retention device to prevent the catheter from being removed from the bladder. In the locked position, the sleeve has been longitudinally moved along the proximal end of the elongated member tube to engage annular step 120 with outside surface 119 in annular recess of collar 114. When the sleeve is pulled, and the member 104 is held fixed, the flexible tension member 121 is drawn through and out of elongated member passageway 107 to close the loop between draw ports 122 and 123, thereby positioning the distal end of the elongated member tube into the pigtail configuration. Retention disk 129 is applied to the outside surface of abdominal wall 130 around the elongated member with tie 125 to more securely position the drainage catheter in the patient. Retention disk 129 is commercially available from a number of sources such as Cook Incorporated, Bloomington, Indiana. Flexible elongated member tube 104 may also be bent to run alongside the patient's body using a 90° retention disk also available from Cook Incorporated.
[0020] Depicted in FIG.4 is an alternative embodiment of the distal end of the drainage catheter. In this particular embodiment, distal end 401 of elongated member 402 of the catheter has been preformed into a well-known configuration for retaining the distal end in the biliary system of a patient. A plurality of drainage ports 403 and 404 have been formed about the distal end and the main body of elongated member 402, respectively.
[0021] Depicted in FIG.5 is a second alternative embodiment of the distal end of the elongated member portion of the drainage catheter. In particular, distal end 501 of elongated member tube 502 has been formed into a pigtail configuration with the distal end extending from pigtail curl 503. Such a configuration is suitable for use as a percutaneously inserted gastrostomy feeding tube.
[0022] The distal end of the catheter may be preformed into any desired configuration for positioning and retaining the distal end of the catheter in any part of a patient's body. Furthermore, the lockable sleeve of the drainage catheter may be designed with an O-ring seal or the like for being locked into associated recesses in the lockable collar and/or the lockable sleeve, and for preventing fluid from passing through the joined or locked interconnection of the sleeve and elongated member. Similarly, a single finger-like projection may extend into a recess formed in the proximal end of the elongated member tube. However, the illustrative embodiment illustrates a drainage catheter which is easily manipulated by the physician without having to tie the flexible tension member. Once in the locked position, the catheter maintains a closed system for which fluid may be drained from the patient. Furthermore, one end of the flexible tension member may be attached in any one of a number of well-known ways to the distal end of the elongated member and drawable through one or more draw ports for positioning the distal end and in the desired position.
1. A medical device comprising an elongated member (104) having a distal end (105),
a proximal end (106), and a passageway (107) extending therebetween, at least the
distal end being for insertion into a patient; and means (121) extending between the
said distal and proximal ends and drawable to reconfigure the distal end into a desired
configuration (FIG.3); characterised in that the device further comprises an elongated
sleeve (110) having distal and proximal ends with a passageway (113) therebetween,
the sleeve being positioned about and longitudinally moveable with respect to and
adjacent to the proximal end of the elongated member; in that the drawable means is
attached to the sleeve; and in that the elongated member within the sleeve and the
interior of the sleeve have co-operating parts (119,120) associated therewith for
engaging the sleeve and the elongated member together when moved relative to one another
to an engaging or interlocking position.
2. A device according to claim 1, characterised in that means (124) are provided for
clamping the drawable member relative to the proximal end of the sleeve; and in that
the relative movement of the distal end of the sleeve towards the proximal end of
the elongated member causes the drawable means to reconfigure the distal end of the
elongated member into the desired configuration.
3. A device according to claim 1 or 2, characterised in that the co-operating parts
comprise an annular ridge (120) on the interior surface of the sleeve, and a co-operating
recess (119) associated with the exterior surface of the elongated member, the relative
movement required to bring the ridge and the recess into co-operative engagement serving
to provide the required movement of the drawable means.
4. A device according to claim 3, characterised in that a collar (114) is provided
about and fixed adjacent to the proximal end of the elongated member, in that the
recess (119) is in the outer surface of the collar, the recess being sized to tightly
receive the said ridge.
5. A device according to claim 4, characterised in that the opening of the ridge has
a dimension less than a maximum outside dimension of the collar in the annular channel.
6. A device according to any one preceding claim, characterised in that the elongated
member comprises, adjacent to the distal end, a plurality of parts (108) for supplying
fluid to, or for draining fluid from, a patient.
7. A device according to any one preceding claim, characterised in that the drawing
means include a flexible tension member extending along the elongated member to at
least one draw port adjacent to the distal end of the member.
8. A device according to any one preceding claim, characterised in that when the sleeve
and elongated member are interlocked, the co-operating parts provide a seal to prevent
leakage of fluid between the elongated member and the sleeve.
9. A method of locating part of a medical device in a patient, said method comprising
the steps of inserting at least the distal end of an elongated member in a cavity
of the patient, and applying tension to a drawable member extending along the elongated
member in order to reconfigure the said distal end into a desired configuration thereby
locking the said distal end within the said cavity, characterised in that the proximal
end of the drawable member is attached to a sleeve longitudinally slideably positioned
about the proximal end of the elongated member, and in that the said tension is applied
by moving the sleeve relative to the elongated member to a position in which the sleeve
and elongated member engage or interlock.